White River Junction — A land use hearing that could lead to a permit for a proposed mixed-use development on Route 4 was caught up in traffic yesterday, as officials and residents worried about the impact of more cars on a major state artery.

Traffic was only one of the 10 issues looked at by the Act 250 commission, a three-member body that reviews large-scale developments for environment impact, but it preoccupied much of the discussion at an otherwise fast-moving hearing.

“This goes to the quality of life that people enjoy,” said Tim Taylor, the commission’s chairman, after learning about increased traffic along Route 4. “Not waiting in lines is part of that.”

The increased flow could come as a result of the Quechee Highlands development, a 168-acre proposal near Exit 1 on Interstate 89 that developer Scott Milne wants to turn into a mix of residential, office and retail space.

During the first phase of development, which would consist of about 120,000 square feet in building construction, about 186 extra cars would pass by on Route 4 during morning rush hour, according to David Saladino of White River Junction-based Resource Systems Group, which completed the traffic study. During afternoon rush hour, as many as 241 more cars could pass by.

According to state data, 1,425 cars traveled that stretch of road during the day’s busiest hour in 2011, although the specific hour wasn’t specified. The traffic study said that the two peak hours were between 7:30 a.m. to 8:30 a.m. and 4:30 p.m. to 5:30 p.m.

The Act 250 commission is tasked only with looking at the first of the three-phase development — for now. Future phases would, among other things, add more residential units. In order to award a permit to Milne, the commission has to find the development to be in full compliance with the 10 criteria, ranging from water safety to the area’s aesthetics.

The traffic criterion is number five, and it was the first that gave the commission pause yesterday.

“It just seems like, ‘It’s lousy and bad, and we’re just going to keep it bad, and maybe it’ll get worse,’ ” Taylor said. “It’s apparent, from what you showed here, that it doesn’t look like the improvements that you’re proposing will ameliorate that in any way.”

Such improvements include monitoring traffic flow at the northbound interstate ramps, and possibly adding a traffic light and a left-turn lane on the highway’s southbound ramps.

“With the mitigation in place, I think we’re resolving any of the implications or impacts of any of the extra traffic,” Saladino said.

Those efforts, at least, were enough to satisfy members of the Hartford Planning Commission. “The traffic issues were settled to our satisfaction,” said commission member John Jalowiec during the meeting. He also agreed that putting the mitigation factors in place was important.

The next hearing, during which additional testimony from the Two Rivers-Ottauquechee Regional Commission will be heard, will be at 5 p.m. on Feb. 21 in the Municipal Building.

Yesterday’s gathering saw more than 30 people pack into the building’s second-floor conference room, an amalgam of architects, members of commissions and abutters.

Chuck Rataj, an abutter, has long been one of the more outspoken opponents of the development. When asked by the commission which of the 10 criteria he found fault, he replied: “All of them. Whole thing.”

Rataj raised concerns about the potential effect on his water supply — the development would draw upon the aquifer rather than tap into the town water system — and the fate of a row of pine trees that provide a visual buffer between his property and the proposed development.

“As long as those existing trees stayed, because they give coverage year round, that would be a huge mitigating factor,” Rataj said.

But not everyone who gave testimony yesterday opposed the development.

Sheryl Trainor, who owns the Quechee Mobil gas station, which would abut the project, said during a break in the hearing that the development would be a boost for her business, which largely caters to tourists fresh off I-89.

“Having people live around your business is very helpful,” she said, referring to the potential residences and businesses that could end up nearby.

Later, the hearing took on a different tenor as architect Joe Greene presented computer-generated renderings of the completed development, which the Act 250 commission had not yet seen.

A PowerPoint presentation turned into a virtual video “drive-through” that traveled around the development’s main circular road, and over the pedestrian walkway that bisects it.

“Looks like Church Street in Burlington,” Rataj whispered.

Rataj’s comment turned out to be prescient. When the video ended, Greene said that, thematically, they were trying to replicate the feel of Church Street in Burlington.

According to Milne, one of the ideas behind the development was to bring a strong retail presence to Vermont, which he said has lost much business to towns in New Hampshire across the Connecticut River.

“Quechee Highlands, in at least a small way, will counter that trend,” he said.

To the Editor: It was with dismay and disbelief that I listened to the proceedings on Feb. 21 in Hartford regarding the proposed Quechee Highlands development. I had been stunned to read the article and see the drawing in the Valley News on Feb. 1; I found it hard to believe that things have gone so far as an Act …